families occur also in this class, although the resemblance chiefly applies to distribution of colour. Take, for instance, some of the Lycidae, and compare them with Paristemia and Paciloderma, two genera of Longicorns, where the colour, although most unusual and startling, is distributed exactly in the same manner, and produces the same effect.

In plants, similar resemblances between distinct orders and families exist. I may refer to the tree-fern (Alsophila) and the Cycad (Stangeria), like each other, and yet belonging to distinct orders; or to the Sesleria cærulea and Carex rupestris; to the Potentilla alpestris and Ranunculus alpestris; to Polygonum Convolvulus and Convolvulus sepium; to Tamarix gallica, and many of the cypresses, or to Calluna vulgaris and Hudsonia ericoides,-all as showing respectively much similarity to each other in the foliage, and yet belonging to different families.

Such are some of the resemblances in the organic creation, which might without impropriety be termed impostures or personations. It is difficult to suggest any probable theory by which they may be accounted for. Some, no doubt, can be explained as being found in species which are the outliers or transitionary links connecting two different orders or families together; as, for instance, Adella frischella and Molanna angustata, connecting the Lepidoptera and Trichoptera; Carex rupestris and Sesleria cærulea, connecting the carices and the grasses, &c. But there remain a vast number of instances which cannot so be disposed of. On what principle are the clear-winged moths, and numerous twowinged flies, invested in the robes of bees? Kirby and Spence thought that the meaning or object of such imitations on the part of some of them (the Volucella for instance, which deposit their eggs as parasites in bees' nests), was to allow of their entering the nest without being discovered. This may be so; and at least in the case of Asaphes, of which I have above spoken, probably is so, although we know that the bees are not very easily deceived, as it is well known that they will not even allow intruders of their own species from a neigh bouring hive to enter with impunity. The fact may be, however, that although we notice them repelling some intruders

from a neighbouring hive, many may enter unnoticed, and in like manner some Volucella may escape detection while others suffer for their intrusion. But admitting it to be so, this only explains the purpose of their being furnished with this livery; it by no means explains the means or law through which they receive it. It may be that if the law (supposing there to be such a law) under which the bees received the creative impulse, and assumed their form and colouring, admitted an influence from the condition and character of their birthplace, the same influence might be extended with a similar effect to the Asaphes and Volucellæ, seeing that the creative birthplace might probably be the same as that of the other, as their actual birthplace in point of fact is. My idea as to this, however, will be better understood after the reader has perused the second part of this inquiry.

But even after accounting for the class of impostors which make some use or profit of their disguise, there remain others, such as the clear-winged moths, still unaccounted for, where not only the colouring of the body, but also the additional transparence of the wings, is had recourse to to complete the deception. Further, there is the case where the same colours similarly and sometimes bizarrely disposed, are repeated in different families of insects. On this point, I may observe, that when such bizarre markings, or similar dispositions of colour occur, it usually (although not invariably) happens that the insects bearing them are from the same country. There are, for instance, several species of Coleoptera from Old Calabar in which singularly distorted angular yellow marks occur on a black ground on the back (Nesioticus flasopictus, Nyctiobates regius, Nyctiobates militaris, &c.); and a Lycus from Jamaica bears exactly the same amount and proportion of colour as Paciloderma terminale, also from Jamaica-a scarlet body with a bright ultramarine tail, and so on. Such singularities suggest two explanations: the one, the possibility of new species arising from hybridisation-and we scarcely yet know enough of the true affinities of the different families of Coleoptera to be able to say whether such hybridisation might be possible or not in the cases I refer to. Another speculation may be, that their creation took place under similar conditions and influence of

locality, which indeed, so far as we know it, corresponds with the present habit of life of the different species alluded to-the larvæ of the Lycide being wood-feeders, like the larvae of the Longicornes, and a similar conformity of habit doubtless also existing between the larvae of Nesioticus and Nyticobates, and of other equally illustrative species which might be mentioned. But let us now turn our attention to those resemblances which consist in an imitation of inanimate objects, or of such animate objects as, from their masses, may in one sense be looked on as inanimate. One very common phase which we find this assume, is a general similitude to the ground on which the animal lives. How closely the colour of our common hare assimilates to the benty braes in which its form is placed; and still more, how the colour of the arctic hare, the polar bear, and other animals which live in the frozen north, fits to their snow-clad land. What a near resemblance does the grouse bear to the heather in which it couches. How well the partridge accords with the general hue of the stubble. How difficult it is to see the ptarmigan beside the gray stones among which it sits. Turning to the water, what more complete match can be found to the sandy bottom of the sea than the back of the flounder or the skate; or to the muddy bottom than the back of the plaice? Look at the tree-frog, so delicately and freshly green, sitting secure among the leaves which he so closely resembles; or at the North American frog, which is found on walls covered with gray lichen, with which he so exactly corresponds, that if he would only sit still no one could see him. Recollect the speckled snakes and serpents, with their coloured patterns so exquisitely blended, and so exactly resembling the tangled herbage through which they glide. Look at the lizards, some of the most lively green, suited to the foliage of the trees on which they live; others gray, like the stones among which they run; or yellow, like the sand on which they bask. Let us not forget the chameleon-which, certainly, whatever be the cause (whether it be an accidental result from mental emotion, an instinctive impulse independent of its will, or a deliberate intention to produce the effect), does exhibit a most striking resemblance in colour to that of the substances on which it rests, and a more marvellous

power of adaptation to the variations in their hue than perhaps any other living creature. Remember the crocodile or alligator floating silently down the muddy stream, so like the trunk of a tree, that the unwary animal drinking on the margin only sees the deception for a moment, when the tree suddenly starts into life, and the victim is hurried below the waters locked in the reptile's formidable jaws. These are examples taken from the vertebrata, but we find similar deceptions repeated, only more frequently and more carefully, in the lower classes of animals. In insects, this is more marked than in any other class. In beetles, the form the deception takes is very frequently that of a pellet of earth or stone (Byrrhida, Ceutorhynchidæ, &c.), sometimes even a piece of silver or copper ore (Chlamyda). We see a small beetle creeping along a plant; we stretch out our hand to take it; at the slightest motion it drops to the ground, its legs and antennæ collapse and are clasped close to its body, and all that remains is a small object, often irregularly marked by prominences, which is so like other little pellets of earth as to be scarcely distinguishable from them, and we only recognise it again by patiently waiting in silence until the insect has regained confidence, when it gradually and timidly protrudes its antennæ and legs, and puts itself in motion. A very common deception among beetles, particularly among the Longicornes, which feed on wood, is to resemble the bark of the trees on which they feed, or, in some instances, the lichens which grow upon them (Rosalia alpina, Prionus cervicornis, &c.) The Orthoptera carry the resemblances they assume more to specific objects. The whole of that tribe partakes more or less of the hue of their dwelling-place. The leaf-insect (Phyllium) is an example which will occur to every one. The Mantis is only a shade less like a leaf; and some are green like a young leaf, others brown and withered like a dried up and decayed one; and in some we find that a change similar to that in the leaf itself takes place; they are fresh and bright green in their youth, but fall into the sear and yellow leaf in the same way and at the same time of year as their prototype. A genus of locusts (Eremobia), which is confined to sandy deserts (Arabia, Egypt, Algeria, Sahara, &c.) furnishes another very striking example. The locusts

found in less arid regions have the colours vivid, the upper wing brown or green, and the lower often bright blue or red. In the desert species, the body and upper wing are subdued to the same tone as that of the sand of the desert, and the lower wing has faded into a pale pink; and this concordance of colour exists in all the Eremobias or desert-livers which have yet been described, the pale pink colour of the under wing only being in one or two species replaced by a similarly faint shade of yellow, which is obviously equally well adapted to the purpose of harmonising with sandy ground, and possibly indicates a yellower tinge in the sand of the particular district which those so coloured inhabit. The orthopterous insects, known as walking-sticks, exhibit an imitation of another character. Their resemblance to dried sticks and straws is most perfect; and their long awkward-looking legs, sprawling in every direction, add to the deception. In their last and complete stage, they have little wings like dried leaves; and in some species, imitations of dried leaves, or rather of broken portions of dried leaves, are also appended to their legs. In the Lepidoptera (more especially the moths), we find not less resemblance to surrounding objects. So much is this the case with them, that few can be found which are not so provided. The great majority pass the day in quiescence, resting on the trunks of trees, under leaves, or on rocks, walls, or stones; and so exactly do they resemble the object on which they rest, that even when we see them fly from one spot to another, and alight under our very eyes, few but an entomologist would detect them. The pattern of speckled gray which generally composes the upper wing, although marked enough when displayed in a cabinet, is in reality a marvel of imitative skill. If any one will take a walk round a country house, and look carefully along the walls, he will probably see a number of moths resting on them, every one so ingeniously deceptive that he will readily admit that he has probably overlooked the half of them. The green and brown hues, imitative of every variety which foliage assumes, speak for themselves, and I therefore pass them over; merely repeating, that the number of insects so coloured is beyond calculation. But it is not only in the perfect state

NEW SERIES.-VOL. XI. NO. I.-JAN. 1860.

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